Editor: Elizabeth Goldbaum
Scientists are using information from NASA’s Earth-observing satellites, on-the-ground sensors and computer-based datasets to study the environmental, economic and societal impacts of the Covid-19 pandemic. In addition, the agency’s Earth Science Division recently sponsored new projects to examine how the shutdowns in response to the pandemic are changing the environment, especially the atmosphere, and determine what, if any, natural environmental phenomena might impact the spread of the pandemic.
“NASA has a unique role to play in response to this crisis,” said John Haynes, NASA’s program manager for Health and Air Quality Applications. “As we continue to collect Earth-observing satellite data on a global scale, we can aid in the understanding of global changes resulting from the pandemic, as well as investigate potential environmental signals that may influence the spread of Covid-19.”
NASA recently funded two new rapid-turnaround projects focused on Covid-19. Jennifer Kaiser at Georgia Institute of Technology in Atlanta and Elena Lind at Virginia Polytechnic Institute in Blacksburg, are examining the pandemic’s impact on air quality related to reduced airport traffic. Joanna Joiner and Bryan Duncan at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, are creating maps and images that show how Covid-19 has reduced air pollution across the world.
Air traffic in the time of COVID-19
“The world’s response to the pandemic is an unintended experiment that is giving us a chance to test our understanding of various air pollution emission sources,” said Barry Lefer, NASA’s program scientist for tropospheric composition.
Kaiser’s research is looking at how Covid-19 travel bans and lockdown orders are impacting air quality around airports. Current conditions create a unique opportunity to study airport-related pollutants, especially nitrogen dioxide and formaldehyde. It’s a footprint that will likely gradually return to its former shape as travel policies are relaxed.
“People are looking at Covid-19 impacts and seeing better air quality with less traffic,” Kaiser said. They might wonder if this is what the future could look like if we relied more heavily on electric vehicles than we do now. Yet, airplanes are not going to be electric anytime soon, Kaiser said.
“Airports are usually some of the hottest spots for nitrogen dioxide,” Kaiser said. Nitrogen dioxide is released when we burn fuel, either in airplanes or cars. When first released into the lower atmosphere, or the part of the atmosphere that we breathe, nitrogen dioxide reacts with other nearby chemicals and forms ozone. Airplane exhaust also forms formaldehyde, which is an indicator of ozone formation and another air toxin. Breathing in ozone can cause chest pain, coughing and throat irritation.
Kaiser and her team installed two sensors at both Baltimore-Washington International Airport (BWI) and Hartsfield-Jackson Atlanta International Airport. BWI’s overall traffic is down by around 60 percent and Atlanta’s is down by 70 percent.
The sensors, which are part of NASA’s Pandora Project, each use a spectrometer to identify chemicals in the air. Two instruments, each propped up with a tripod, sit at both airports. Their spectrometers use ultraviolet and visible wavelengths of light to detect ozone, nitrogen dioxide and formaldehyde at different altitudes of the atmosphere.
Kaiser is comparing the on-the-ground sensor information with satellite information from the European Space Agency (ESA)’s TROPOspheric Monitoring Instrument (TROPOMI), aboard the Copernicus Sentinel-5 Precursor satellite, launched in 2017 and managed by the European Commission in partnership with ESA, the EU Member States and EU agencies. She wants to know if we’re understanding the satellite data accurately for these locations by ground truthing them with the newly-installed Pandora sensors.
“We want to help our stakeholders, like policymakers, improve their understanding of the air we breathe,” Kaiser said, and how that air can be affected by pollution from airports.